A cafe in Sydney's south-west has been destroyed by a large, loud explosion overnight. The blast happened just after midnight at a Panania pizza and kebab cafe on Anderson Avenue. It sent the cafe's roller door flying into the air and shattered many nearby shop windows. New South Wales Fire Brigade Superintendent Ian Krimmer says it was a massive blast. "As a result of the incident there was a subsequent fire which threatened to spread to several adjoining buildings," he said. "Fire crews were on scene within eight minutes - they had quickly contained the fire to the building origin."He says the explosion damaged buildings 50 metres away. "There is a fair amount of debris and bricks that have fallen onto the roadway in front of this particular shop," Supt Krimmer said. The cause of the explosion is yet to be determined. Police are asking people who own businesses in the vicinity of Panania Post Office to contact Bankstown or Revesby police about securing their property.